Michael, I looked around the net and didn't find anything of value so I suggest you call Pioneer at 800-pioneer and they might be able to help you. This was from Pioneer's first generation of Elite Dolby Digital receivers [at least as a complete line-up] and a very good unit for it's time. It is similar to the 606 but with a better power supply and nicer looking. That 1997 line of Pioneer and Elite's was what drew me to Pioneer . I had a 906 and loved it. It was much better than any other reciever I heard at the dawn of Dolby Digital and miles better than the Yamaha 992 and Onkyo 747 I had before. If you have a chance to get the 05 for a low price I would do so but realize it lacks many features common on today's models.